cl20: Reuse test harness code in conversions (#178)
cl20: Reuse test harness code in conversions (#178)

Some of the setup functionality is already there in the test harness, so
use that and remove the duplicated code from within the suite.

Signed-off-by: Radek Szymanski <a46b38089acf8d5419512b5627d21e7e565f2048@arm.com>
KhronosGroup/OpenCL-CTS,KhronosGroup/OpenCL-CTS,KhronosGroup/OpenCL-CTS,KhronosGroup/OpenCL-CTS